The Post reported the allegations Friday, with the players requesting anonymity because of the sensitivity of the topic. A league source informed The Post of the NFL's plans to investigate Saturday. It is standard operating procedure to look into any accusations that NFL rules have been broken.

League spokesman Greg Aiello declined to comment on the matter when reached by NFL.com and NFL Network.

The Post's report described a system under Williams in which he paid out thousands of dollars to his players for hits such as "kill shots."

"You got compensated more for a kill shot than you did other hits,â one former player told The Post on condition of anonymity.

Joe Gibbs, who was the Redskins' head coach when Williams was the team's defensive coordinator, said he was shocked to learn of the allegations Friday, and he was unaware that such a program existed during his second stint in Washington.

"Just let me say this: Iâm not aware of anything like this when I was coaching there," Gibbs told the Post. "I would never ask a player to hurt another player. Never."

Former Redskins defensive back Matt Bowen, who played under Williams in 2004 and 2005, wrote a column in Friday's Chicago Tribune detailing his involvement in Washington's "bounty" system.

"It was a system we all bought into," Bowen wrote. "I ate it up. It's hard not to, not when you're playing for a coach like Gregg Williams, my defensive coordinator while I was with the Washington Redskins.

"Williams is an excellent motivator. You do what he wants: play tough, push the envelope and carry a swagger that every opponent sees on tape. When you lined up against us, you knew we were coming after you. It was our gig, our plan, our way to motivate, to extra-motivate."